• As millions of stimulus checks go out, surveys show some people plan to invest the money.
• Experts have issued cautions about what kind of holdings to acquire.
• Another thing to consider is the type of account you open, and how long you plan to hold on to that money.

A new set of $1,400 stimulus checks may tempt some recipients who don't really need the money to instead dabble in the stock market.

Depending on your goals, a brokerage account may not be your best bet, some experts say.

A third round of direct payments was authorized by Congress and President Joe Biden last month through the American Rescue Plan Act.

The payments are up to $1,400 per person, plus $1,400 per eligible child or adult dependent.

Like the first two direct checks, the money is designed for individuals and families who meet certain income and other requirements.

And as with those past payments, the money is not necessarily targeted. So the funds will go to people who have been hit hard by the pandemic, as well as those whose incomes have not been interrupted.

More from Personal Finance:
About 127 million $1,400 stimulus checks have been sent
Using tax-deferred savings can help you get that $1,400 stimulus check
How to make sure you don't miss $1,400 stimulus checks in the mail

For people in the latter camp, it may be tempting to try to make the money grow.

A recent survey from Deutsche Bank found that many young retail investors who already use online brokerage platforms plan to spend part of their money on stocks.

How much those investors planned to allocate to the markets varied by age, the survey found.

Those between ages 25 and 34 planned to spend 50% of their stimulus checks on stocks. That went down to 40% of the money for 18- to 24-year-olds and 37% for 35- to 54-year-old investors.

The urge to invest has prompted experts to try to steer investors to make wise decisions with the money.

CNBC's Jim Cramer advised that, after people pay their bills, they should put most of the money in an S&P 500 index fund. At least $10,000 should be invested in one of those low-cost funds before investors acquire positions in individual stocks.

Rithholtz Wealth Management CEO Josh Brown, who is also a CNBC contributor, recently wrote a blog post urging people to stay away from speculative investments.

"Do not buy SPACs, digital currencies or non-fungible tokens sold to you by millionaires and billionaires with your stimulus check," Brown wrote.

Some stimulus check recipients have been lured by features offered by fintech startups to make accessing the money more convenient. For example, one Robinhood feature gives traders bonuses for new deposits.

But while much advice has focused on how to invest the stimulus checks, less attention has focused on where to invest it.

"Where you put it and how you invest it are two different things," said Ed Slott, CPA and founder of Ed Slott & Co.

When deciding where to store your money, people may want to consider using traditional or Roth individual retirement accounts instead of a brokerage account, Slott said.

One key question to ask is how long the money will be in that account.

If it's a short-term investment, where an investor plans to go back and forth, it may be better to keep it in a brokerage account where it can be withdrawn without any penalties.

But it's also important to keep in mind the tax implications for that money, which is where an IRA could be more advantageous, Slott said.

If you hold stocks for more than a year, long-term capital gains rates apply. But for any time horizon shorter than that, it will be taxed at ordinary rates.

"The benefit of the IRA is it's more geared towards long term," Slott said.

Roth IRAs, where post-tax money is invested, may offer the most potential upside in this situation, according to Slott.

With a Roth, trading done inside the account is not reportable, so the money can be withdrawn tax-free, so long as certain conditions are met. (Generally any earnings cannot be taken out until it's been five years since the Roth IRA contribution was made, for example. Certain penalties may also apply if you're under age 59½.)

With a traditional IRA, any trading inside the IRA would also not be tracked, but the account owner would have to pay taxes on the money upon withdrawal.

Ideally, investors will leave the money where it is in order to let it grow.

"If you can hold on long term, you have big gains over time," Slott said.